That same study found public transit trips in the U.S. increased by 1.5 percent in 2012. Many rail and bus services showed double-digit increases that year compared to 2011.

Ridership for the Metropolitan Transit System, or MTS, which serves San Diego, was down 0.22 percent. Trolley trips, meanwhile, fell by 4.71 percent.

Rob Schupp, a spokesman for the MTS, said one reason for this has been construction aimed at improving light-rail service.

"We've had a lot of construction impacts," said Schupp. "We've actually shut down the blue line on weekends. So those have an impact on our ridership numbers."

Schupp added that the MTS's trolley rider estimates, which formed the basis for the 2012 numbers, are also not the best method for counting trips.

"We now have automated passengers counters on board our trollies," he said, "so we're changing that methodology to a system that we think might be more accurate and reflect a truer ridership for the trolley."

The American Public Transportation Association ridership numbers for the North County Transit District, serving north San Diego County, were more reflective of national trends. Overall transit use for the NCTD went up 3.13 percent.

Yes, other than stops downtown, the trolley barely connects to anything. I feel like it completely sidesteps the neighborhoods with the population most likely to use it, i.e The uptown district neighborhoods.